Lock plug shell

ABSTRACT

A lock plug shell providing an unlatching button for push button equipped door latches. The shell is of hard flexible resilient material and includes a cam engagable with and displaced by the retaining lug of a cylinder lock plug during movement of the lock plug toward its normal operating position in the shell, the shell having sufficient resilience to dispose a portion of the cam in a position to prevent accidental removal of the lock plug from the shell when the lock plug is moved to its operating position in the shell.

United States Patent Engstrom Sept. 12, 1972 1 LOCK PLUG SHELL 72 Inventor: George L. Engstrom, 3558 Tyler 51.,

NE, Minneapolis, Minn. 55418 [22] Filed: Jan. 8, 1971 21 Appl.No.: 105,118

Related U.S. Application Data [63] Continuation of Ser. No. 877, Jan. 6, 1970,

abandoned.

[52] U.S. Cl ..70/373, 70/360, 292/DIG. 37,

292/DIG. 38

[51] Int. Cl. .Q ..E05b 9/02 [58] Field of Search ..70/360, 367-371, 70/373, 375, 422; 292/DIG. 37, DIG. 38

[56] References Cited UNITED STATES PATENTS 3,039,804 6/1962 Quinn ..29 2/254 2,803,716 8/1957 Nolden ..70/371X Ryder ..70/ l 39 Jacobi ..70/373 Primary Examiner-Robert L. Wolfe AttorneyMerchant & Gould [57] ABSTRACT A lock plug shell providing an unlatching button for push button equipped door latches. The shell is of hard flexible resilient material and includes a cam engagable withv and displaced by the retaining lug of a cylinder lock plug during movement of the lock plug toward its normal operating position in the shell, the shell having sufficient resilience to dispose a portion of the cam in a position to prevent accidental removal of the lock plug from the shell when the lock plug is moved to its operating position in the shell.

8 Claims, 7 Drawing Figures PATENTEDSEPIZ m2 3.690.132

INVENTOR. GEORGE L.ENG$THOM RTTORNEYS BACKGROUND OF THE INVENTION Door latches having push type unlatching buttons are well known, including those in which the rigid cast metal unlatching buttons or shells are provided with key operated cylinder locks for locking the push buttons against unlatching movement. Normally, the cylinder locks, commonly referred to as lock plugs, are axially slidably inserted into bores in the shells, with one of the keys for the lock inserted in the plug, for shipment. With this procedure, loss or mix-up of keys is avoided. However, during shipment and handling prior to and during installation of the latches on doors, the lock plugs, with their keys attached, become disassembled from their respective shells, resulting in considerable inconvenience and annoyance to persons installing thelatches.

SUMMARY OF THE INVENTION The unlatching button or lock plug shell of' this invention is of molded construction, preferably using synthetic plastic material to provide a shell like hard, flexible and resilient body adapted to be slidably movably mounted in a latch handle or like member for recipricatory movements therein between door latched and unlatched positions. The body has a generally cylindrical bore therethrough from its inner end to its outer end for reception of a cylinder lock plug, the bore having a diametrically enlarged portion adjacent-the inner end of the body cooperating with the bore to define a circumferentially extending shoulder. The body furtherdefines a channel that opens radially into the bore. and extends in a direction axially from the shoulder to the outer end of the body. The channel provides a passage for a retaining lug on the lock plug, the retaining lug engaging the shoulder when the plug is fully inserted in the bore and rotated. A stop lug is formed in the enlarged bore portion adjacent one side of the channel and the body is formed to provide a cam in the enlarged bore portion adjacent the other side of the channel, The cam defines a cam surface that engages the lock plug retaining lug when the lock plug is rotated toward its operating'position, and an abutment surface angularly displaced from the cam surface to limit rotary movement of the lock plu n a direction which would enable the same to be removed from the bore. The flexibility and resilience of the shell body enables the cam to be displace by the lock plug retaining lug when the lock plug is rotated toward its operating position, and to return to a normal condition when the retaining lug passes beyond the cam surface, to dispose the abutment surface in the path of rotary movement of the retaining lug in the opposite direction toward the channel.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary horizontal section through a door and door frame, and latch means embodying the lock plug shell of this invention;

FIG. 2 is a fragmentary vertical section taken substantially on the line 2--2 of FIG. 1;

FIG. 3 is an enlarged view in end elevation of the lock plug shell, as seen from the left to the right with respect to FIG. 2;

FIG. 4 is a view corresponding to FIG. 3 but showing a different position of some of the parts;

FIG. 5 is a longitudinal section taken substantially on the line 5-5 of FIG. 3;

FIG. 6 is a view corresponding to FIG. 5 with some parts removed; and v FIG. 7 is a longitudinal section taken on the line 7-7 of FIG. 3, some parts being removed.

DETAILED DESCRIPTION A conventional door 1 and door frame 2 are shown fragmentarily in FIGS. 1 and 2, the free edge portion 3 of the door 1 engaging a side jam portion 4 of the door frame 2 when the door 1 is in a closed position, as shown in FIG. 1.

The lock plug shell or unlatching button of this invention is used with latches of the general type disclosed in U. S. Pat. No. 3,039,804, issued to Bert A. Quinn. Such a latch mechanism is shown in FIGS. 1 and 2 as comprising, a pair of latch hooks 5, one of which is shown, integrally formed with an inner base member 6, an outer base member 7 formed to provide a depending outer handle 8, a retractable strike element 9, and an unlatching member 10 having a handle portion 11 and pivotally mounted between the latch hooks 5 as indicated at 12. The strike 9 is yieldingly urged toward engagement with the latch hooks 5 by a pair of coil compression springs 13, one of which is shown in FIG. 1, and is moved out of latching engagement with the hook elements 5' by swinging movement of the unlatching member 10. As shown in FIG. 2, the base members 6 and 7 are mounted on opposite sides of the door 1 by means of a pair of mounting screws 14. A rotary locking member 15 is mounted in the inner base member 6 for rotary movement of a portion of the member 15 into and out of the path of travel of a lug 16 on the unlatching member 10 to hold the member 10 against movement toward the yieldable strike element 9. The latching mechanism thus far described is fully shown and described in the above identified Quinn patent and, in and of itself, does not comprise the instant invention. Hence, in the interest of the brevity, further detailed showing and description thereof is omitted.

An elongated cross-sectionally rectangular latch releasing spindle 17 extends transversely through aligned openings 18 in the door 1 and has its inner end portion 19 mounted in the locking member 15 for common rotary movement therewith and for axial sliding movements with respect thereto. The inner end portion 7 19 of the spindle 17 is engagable with the unlatching member 10 to move the same in an unlatching direction toward the strike element 9 upon inward movement of the spindle 17. The spindle 17 is formed to provide an enlarged outer end 20 that is mounted in the inner end of a conventional cylinder lock plug 21 that is mounted in the unlatching pushbutton or lock plug shell of this invention, indicated generally at 22. The lock plug shell 22 is mounted in the outer base member 7 for sliding movements toward and away from the door 1 and longitudinally of the spindle 17. A coil compression spring 23 is interposed between the door 1 and the outer end 20 of the spindle 17 to I yieldingly urge the spindle 17, lock plug 21 and shell 22 in an outward direction away from engagement of the inner spindle end portion 19 with the adjacent portion of the unlatching member 10. The unlatching button or lock plug shell 22 is in the nature of a hollow body having an open inner end 24 and a closed outer end 25, the inner end 24 including a flange 26 that engages an inner wall surface portion 27 of the outer base member 7 to limit outward movement of the shell 22, as shown in FIG. 2..The shell 22 is further formed to provide a bore 28 in which the lock plug 21 is rotatably mounted. Adjacent the inner end 23, the bore 28 has a diametrically enlarged bore portion 29 which cooperates with the bore 28 to define an axially inwardly facing circumferentially extending shoulder 30. The bore 28 is counterbored at its end adjacent the outer wall 25, as indicated at 31, for reception of an end flange or cap portion 32 of the lock plug 21. The lock plug 21 is of the well known variety in common use, having an axial slotlike opening 33 for reception of a key shown by dotted lines in FIG. 2 and indicated at 34, and a plurality of key actuated tumblers 35. Adjacent its inner end, the lock plug 21 is provided with an axially extending radially outwardly projecting retaining lug 36.

The shell 22 is formed to provide a pair of upper and lower axially extending channels 37 and 38 that extend axially of and open radially inwardly to the bore 21. As shown particularly in FIGS. -7, the channel 37 extends from the outer end 25 or counterbore 31 axially inwardly, terminating in spaced relationship to the shoulder 30. The lower channel 38 is open ended, extending from the counterbore 31 to the shoulder 30. The shell 22 is further formed to provide an axially extending stop lug 39 that projects radially inwardly from the diametrically enlarged bore portion 29 adjacent one side of the channel 38, see particularly FIGS. 3, 4 and 7. A cam 40 projects radially inwardly from the enlarged bore portion 29 adjacent the opposite side of the channel 38 and has a cam surface 41 that slopes generally radially inwardly and circumferentially away from the groove 38, see particularly FIGS. 3, 4 and 6. With reference to FIGS. 3 and 4, it will be seen that the cam 40 projects radially inwardly from the enlarged bore portion 29 a distance slightly less than the width of the shoulder 30. The cam 40 includes an abutment surface 42 that is angularly displaced from the cam surface 41, for a purpose which will hereinafter be described.

In assembling the lock plug 21 and shell 22, the key 34 is first inserted into the slot 33 of the lock plug 21 to draw the tumblers 35 radially inwardly. The lock plug 21 is then inserted into the bore 28 with the retaining lug 36 disposed in the lower channel 38. The lock plug 21 is moved axially inwardly until the head 32 thereof is seated in the counterbore 31 at which point the retaining lug 36 will be disposed just beyond the plane of the shoulder 30 of the shell 22. With reference to FIG. 3, it will be seen that, when the lock plug 21 is inserted into the shell 22 the retaining lug 36 is disposed between the stop lug 39 and cam 40, in alignment with the lower channel 38. In order that the lock plug 21 can be disposed in its operating position and held against axial withdrawal from the shell 22, the lock plug 21 must be rotated to bring the retaining lug 36 circumferentially beyond or above the stop lug 39 and cam 40. In order to achieve this end, the shell 22 is molded of hard flexible resilient material, such as one of the readily available synthetic plastic materials. With reference to FIGS. 3 and 4, it will be seen that, when the lock plug 21 is rotated in a direction to move the retaining lug 36 over the cam surface 41, the adjacent portion of the shell 22 will flex or distort sufficiently to move the cam 40 out of the path of rotary movement of the retaining lug 36. When the retaining lug 36 has moved beyond the cam 40 in a counterclockwise direction with respect to FIG. 4, the inner end of the retaining lug 36 will engage the shoulder 30 to prevent axial withdrawal of the lock plug 21, and the lock plug 21 will be free to rotate within the limits provided by the abutment surface 42 ofthe cam 40 and the stop lug 39. This amount of rotation is at least degrees of circular movement of the lock plug 21, which is sufficient to rotate the spindle 17 and locking member 15 between the locking and release positions thereof. With further reference to FIG. 3, it will be seen that the opposite sides of the stop lug 39 are disposed radially of the bore 28 to positively stop rotary movement of the lock plug 21 upon engagement of the retaining lug 36 with either side of the stop lug 39. The abutment surface 42 of the cam 40 is normally angularly disposed with respect to a radius of the bore 28 extending therethrough. This angular disposition of the surface 42, coupled with the generally semicylindrical surface of the retaining lug 36, indicated at 43, permits the lock plug 21 to be rotated from its operating position to its insertion or withdrawal position wherein the retaining lug 36 is disposed in alignment with the channel 38, when it is desired to remove the lock plug 21 from the shell 22. The angular displacement of the abutment surface 42 is such that a substantial amount of turning force must be applied to the lock plug 21 to distort the shell 22 sufficiently to enable the retaining lug 36 to pass in this reverse direction over the cam 40. Thus, once the lock plug 21 is inserted into the shell 22 and rotated to its operating position therein, it is effectively retained within the shell 22 against accidental removal.

What is claimed is:

1. A lock plug shell for push type door latches; said shell comprising a hard flexible resilient body having a cylinder lock plug receiving bore therethrough; said bore having a diametrically enlarged inner end portion cooperating with the bore to define an annular shoulder, and an outer end; said body defining a channel opening radially into said bore and extending axially of the bore from said shoulder to the outer end of the bore; a stop lug in said enlarged bore portion; and a cam in said enlarged bore portion in circumferentially spaced relation to said stop lug, said channel being disposed circumferentially between said stop lug and cam; said cam defining a cam surface sloping generally in a direction angularly inwardly from said enlarged bore portion and circumferentially away from said channel.

2. A lock plug shell for push type door latches; said shell comprising a hard flexible resilient body having a cylinder lock plug receiving bore therethrough; said bore having a diametrically enlarged inner end portion cooperating with the bore to define an annular shoulder, and an outer end; said body defining a channel opening radially into said bore and extending axially of the bore from said shoulder to the outer end of the bore; a stop lug projecting radially inwardly of said cam is integrally formed with said body and projects radially inwardly of said enlarged bore portion a distance slightly less than the width of said shoulder.

4. The lock plug shell defined in claim 3 in which said cam defines an abutment surface angularly displaced from said cam surface for engagement with a retaining lug of a cylinder lock plug received in said bore to limit rotary movement of the lock plug in one direction.

5. A lock plug shell for a push type door latch, the door latch including, a handle mounting a shell for reciprocatory movements between door latched and door unlatched positions, and yielding means urging the shell toward its door latched position; said shell having inner and outer ends and a lock plug receiving bore extending therethrough from one of its ends to the other thereof, said bore having a diametrically enlarged portion adjacent the inner end of the shell and cooperating with the bore to define a circumferentially extending shoulder, the shell defining an open ended channel in the surface of said bore extending longitudinally of the bore from said shoulder to the opposite end of the bore for reception of a radially outwardly projecting retaining lug on a lock plug in said bore, said shoulder engaging the retaining lug responsive to axial and. rotary movement of the lock plug to hold the retaining lug in said enlarged bore portion when the lug is angularly displaced from said groove, stop means in said enlarged bore portion for engagement with the retaining lug to limit rotation of the lock plug in one direction, and cam means in said enlarged bore portion in the path of rotary movement of the retaining lug and circumferentially spaced from said stop means, said shell being of hard resilient material having sufficient flexibility to be generally radially displaced at said cam means by the retaining lug during rotation of the lock plug in one direction to move the retaining lug away from said groove, said shell having sufficient rigidity to prevent accidental movement of the lock plug retaining lug over said cam means upon rotation of the lock plug in the opposite direction.

6. The lock plug shell defined in claim 5 in which said stop means comprises a stop lug integrally formed with said shell in said enlarged bore portion adjacent one side of said channel, said cam means comprising a cam element integrally formed with said shell in said .enlarged bore portion adjacent the opposite side of said channel.

7. The lock plug shell defined in claim 6 in which said cam element projects radially inwardly of said enlarged bore portion a distance slightly less than the width of said shoulder.

8. The lock plug shell defined in claim 7 inwhich said cam element defines a surface sloping generally in a direction angularly inwardly from said enlarged bore portion and circumferentially away from said channel.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No, 3,690,132 Dated ptember 12, 1972 Inventor-(s) George L. Engstrom It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On theTitle-Abstract page, add

- [73] Assignee: Ideal Security Hardware Corporation St. Paul, Minn.

Signed and sealed this 13th day of-March 1973.

(SEAL) Attest:

EDWARD .M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents F ORM PO-1050 (10-69) USCOMM-DC 60376-P69 w u,s. GOVERNMENT PRINTING OFFICE X989 0-366-334, 

1. A lock plug shell for push type door latches; said shell comprising a hard flexible resilient body having a cylinder lock plug receiving bore therethrough; said bore having a diametrically enlarged inner end portion cooperating with the bore to define an annular shoulder, and an outer end; said body defining a channel opening radially into said bore and extending axially of the bore from said shoulder to the outer end of the bore; a stop lug in said enlarged bore portion; and a cam in said enlarged bore portion in circumferentially spaced relation to said stop lug, said channel being disposed circumferentially between said stop lug and cam; said cam defining a cam surface sloping generally in a direction angularly inwardly from said enlarged bore portion and circumferentially away from said channel.
 2. A lock plug shell for push type door latches; said shell comprising a hard flexible resilient body having a cylinder lock plug receiving bore therethrough; said bore having a diametrically enlarged inner end portion cooperating with the bore to define an annular shoulder, and an outer end; said body defining a channel opening radially into said bore and extending axially of the bore from said shoulder to the outer end of the bore; a stop lug projecting radially inwardly of said enlarged bore portion adjacent said shoulder and oneside of said channel, and a cam projecting radially inwardly of said enlarged bore portion adjacent said shoulder and the opposite side of the channel; said cam defining a cam surface sloping generally in a direction angularly inwardly from said enlarged bore portion and circumferentially away from said channel.
 3. The lock plug shell defined in claim 2 in which said cam is integrally formed with said body and projects radially inwardly of said enlarged bore portion a distance slightly less than the width of said shoulder.
 4. The lock plug shell defined in claim 3 in which said cam defines an abutment surface angularly displaced from said cam surface for engagement with a retaining lug of a cylinder lock plug received in said bore to limit rotary movement of the lock plug in one direction.
 5. A lock plug shell for a push type door latch, the door latch including, a handle mounting a shell for reciprocatory movements between door latched and door unlatched positions, and yielding means urging the shell toward its door latched position; said shell having inner and outer ends and a lock plug receiving bore extending therethrough from one of its ends to the other thereof, said bore having a diametrically enlarged portion adjacent the inner end of the shell and cooperating with the bore to define a circumferentially extending shoulder, the shell defining an open ended channel in the surface of said bore extending longitudinally of the bore from said shoulder to the opposite end of the bore for reception of a radiallY outwardly projecting retaining lug on a lock plug in said bore, said shoulder engaging the retaining lug responsive to axial and rotary movement of the lock plug to hold the retaining lug in said enlarged bore portion when the lug is angularly displaced from said groove, stop means in said enlarged bore portion for engagement with the retaining lug to limit rotation of the lock plug in one direction, and cam means in said enlarged bore portion in the path of rotary movement of the retaining lug and circumferentially spaced from said stop means, said shell being of hard resilient material having sufficient flexibility to be generally radially displaced at said cam means by the retaining lug during rotation of the lock plug in one direction to move the retaining lug away from said groove, said shell having sufficient rigidity to prevent accidental movement of the lock plug retaining lug over said cam means upon rotation of the lock plug in the opposite direction.
 6. The lock plug shell defined in claim 5 in which said stop means comprises a stop lug integrally formed with said shell in said enlarged bore portion adjacent one side of said channel, said cam means comprising a cam element integrally formed with said shell in said enlarged bore portion adjacent the opposite side of said channel.
 7. The lock plug shell defined in claim 6 in which said cam element projects radially inwardly of said enlarged bore portion a distance slightly less than the width of said shoulder.
 8. The lock plug shell defined in claim 7 in which said cam element defines a surface sloping generally in a direction angularly inwardly from said enlarged bore portion and circumferentially away from said channel. 